Partner in a nest on fire (8)
I believe the answer is:
animated
'on fire' is the definition.
Both the definition and answer are adjectives. Maybe you can see a link between them that I don't see?
'partner in a nest' is the wordplay.
'partner' becomes 'mate' (synonyms).
'in' means one lot of letters goes inside another.
'nest' becomes 'nid' (I've seen this in another clue).
'a'+'nid'='anid'
'mate' placed inside 'anid' is 'ANIMATED'.
Can you help me to learn more?
(Other definitions for animated that I've seen before include "put in spirit" , "full of beans" , "Vivacious in diamante" , "Lively - like cartoon films" , "Diamante (anag)" .)